Stroke is the third leading cause of death and the first cause of acquired physical or cognitive impairment in developed countries. Strokes are ischaemic in 80% of cases and the leading causes are atheroma and cardiac emboli. But despite extensive investigation, up to 40% of cases remain without definite actiology.
Familial causes of stroke have recently been identified, such as MELAS and homocystinuria. Since 1977, nine unrelated families have been reported with a new mendelian syndrome that leads to stroke. Recently a pedigree was reported, the large size of which allowed the precise definition of the clinical, neuro-imaging and genetic parameters of this disease (Tournier-Lasserve et al, Stroke, 1991, 22, 1297-1302, Tournier-Lasserve et al, Nature Genetics, 1993, 3, 256-259). This condition is characterized by recurrent subcortical ischaemic strokes and dementia. It is underlaid by a cerebral non-atherosclerotic, non-amyloid angiopathy affecting mainly the small arteries penetrating the white matter and basal ganglia. All reported families share strikingly similar clinical, neuro-imaging and pathological features. The acronym CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy) is used.